I need to power a gadget I am building with 5 x AA batteries (6V), but I also want to be able to recharge it via USB (5V) while the gadget is on (that is, I want to be able to plug and unplug the USB cord freely, without the need to remove the battery or turn the device off).
I have read a lot already about this, but there seem to be so many options to choose from that I am rather confused.
So the core of my question is:
Is there any well-known off-the-shelf component or IC to boost 5V from USB to (more than) 6V so I can charge the pack?
As an example of what I understand as "well known off the shelf component", I could mention "4017" as counter, "555" as timer/oscillator, "7806" as voltage regulator, etc. It's something I could find and use easily and cheaply.